Study: not all obese people face higher heart disease risk

A small proportion of obese people may not face a higher risk for diabetes and heart disease often associated with obesity, according to new research presented this past weekend at a meeting of the Endocrine Society in San Diego. In a long-term study that included more than 1,300 obese patients between the ages of 28 to 75, researchers identified 90 study participants who they characterized as metabolically healthy — or lacking risk factors such as high blood pressure, high cholesterol, or history of heart disease. In this small group (representing just 6.8% of the total study population), researchers found that, after more than seven years of follow-up, incidence of heart disease and diabetes was similar to that for overweight or normal weight peers.

The long-term analysis, conducted by researchers from the Netherlands’ University Medical Center Groningen, analyzed weight and cardiovascular health for more than 8,300 individuals participating in the Prevention of Renal and Vascular Endstage Disease (PREVEND) study. Researchers followed study participants for 7.5 years. During this time period, 0.6% of normal weight participants developed heart disease or diabetes, 1.3% of overweight participants did, and 1.1% of obese patients categorized as metabolically healthy developed the conditions.

Based on these findings, the researchers conclude that the link between obesity and risk for heart disease and diabetes may be determined by metabolic risk factors, not solely weight. Even so, they are quick to emphasize that the findings only refer to a very small proportion of the obese population, and that routine check-ups to determine any changes in risk are still important.

While that is certainly promising news for obese individuals without certain risk factors — including history of heart disease, high cholesterol and use of cholesterol-lowering medications — some obesity researchers question whether the study’s follow-up period was long enough to accurately reflect long-term risk for cardiovascular disease or diabetes associated with obesity. As Dr. Gregg C. Fonarow, director of the Ahmanson-UCLA Cardiomyopathy Center at the University of California, Los Angeles, told HealthDay:

“While this study did not find increased risk associated with obesity if no metabolic abnormalities were present, it is important to note that other studies with longer-term follow-up have shown there is an increased risk of cardiovascular events in these individuals… The balance of evidence suggests that, over the long-term, obesity imparts higher cardiovascular risk, even if metabolic abnormalities are not present at baseline.”